It has to do with a current known as Florida's Gulf Stream.
The Gulf Stream is borne between Key West and Cuba, and it's probably better known for transporting warmth to the Northeastern United States, Canada and Europe. This single current carts some 90 trillion tons of water an hour, according to a 1930 Popular Mechanics report that described it, at its birthplace, as a “rushing torrent larger than 10 Mississippi rivers.”
If the Gulf Stream stalled or stopped flowing, some say, an ice age – or “little ice age” could set in. That was the premise of the 2004 movie, "The Day After Tomorrow."
Warming and cooling periods throughout the world happen naturally and in cycles that are gradual, in part as a result of the earth's rotation and the sun's energy, experts suggest. Continents naturally shift, and cooler eras seem to happen after they collide, according to Kirk A. Maasch, a University of Maine Geological Sciences Professor. But ice ages happen about every 200 million years and last millions of years, Maasch notes.
The ocean, on the other hand, holds the majority of the earth's heat – and it could cause noticeable climate changes in as few as 10 years that could go on for centuries, according to the Woods Hole Oceanographic Institute in Massachusetts.
Winds move tepid waters near the top of the Gulf Stream, while cool, salty waters sink and become a lower river, according to NASA and Woods Hole Oceanographic. The warmer seas become, the more moisture and evaporation results, Woods Hole information suggests.
For northern regions, that could mean more showers that are lighter than salt water. If they don't sink the way their thicker, salty counterparts do, the Gulf Stream could stall or stop moving, Woods Hole suggests. Seas deepened from the rain, along with melted glaciers, could in turn become colder, the organization notes.
The Gulf Stream, and current weather patterns, might have once been vastly different.
That's because the Gulf Stream is part of a “conveyor belt” of waters that generally begin with those said to be from the fresher, deeper and cooler Indian and South Pacific oceans. Waters from these oceans trek toward South Africa, slip up into the Caribbean Sea, loop around the Gulf of Mexico and head down along Florida's west coast before they funnel in to the Gulf Stream, an American Meteorological Society map shows.
A “Continental Divide” keeps conveyor belt waters on track. But at one point, a wide seaway between North and South America allowed waters to flow between the warmer, saltier Atlantic and the cooler, fresher, Pacific, according to a 2008 Florida Museum of History study. Then, millions of years ago, the continents collided, and Panama began blocking that flow, the museum study noted. With the Americas joined, ocean currents changed and ushered enough moisture northeast that glaciers were able to form, the Florida Museum researcher contends.
It was during a glacial period, archaeologists say, that seas receded and the former reefs and shoals that are the Florida Keys emerged.
Dangling south west from mainland Florida, they gently curve around the Gulf Stream.
About Historic Walking Guides: Florida Keys
Historic Walking Guides: Florida Keys takes readers back in time as they travel off the beaten path from the edge of Florida's mainland to Key West. In Key West, readers can embark upon a series of historic walking tours, each centered around themes such as treasure hunting, commercial fishing, literary luminaries and, of course, two of the best known residents of all -- Ernest Hemingway and Jimmy Buffett. Historic Walking Guides: Florida Keys is available in print through Destinworld Publishing and Amazon.com. It's expected to be in digital format in early 2011.
Historic Walking Guides: Florida Keys takes readers back in time as they travel off the beaten path from the edge of Florida's mainland to Key West. In Key West, readers can embark upon a series of historic walking tours, each centered around themes such as treasure hunting, commercial fishing, literary luminaries and, of course, two of the best known residents of all -- Ernest Hemingway and Jimmy Buffett. Historic Walking Guides: Florida Keys is available in print through Destinworld Publishing and Amazon.com. It's expected to be in digital format in early 2011.
